Sunday, September 25, 2011

Not much to cheer about

It's been one of those weekends. Driving home from the paying gig an Friday afternoon, I felt the usual small uplift in mood that precedes a couple days of not having to deal with the traffic and other associated hassles that come from having to interact with the rest of humanity. Nope, weekends usually offer up the promise of minimal computer help desk issues (supporting a handful of family/friends with their computer problems is so much easier than supporting three dozen), quiet relaxation around the house with the family, and a chance for some gratifying work on the airplane. It's the latter, I think, that clears my mind the most.

The paying job is probably better than most for providing some level of "job well done" satisfaction, but it's all so... intangible.  I'll spend hours developing an eloquent solution for someone else's work need, and every now and then spend even more hours re-doing it because they didn't like the result. I also spend hours adding in little convenience factors (remembering window sizes and positions, configuration settings, etc.) that they won't even notice as these little gems smooth out their work day.  That's all well and good, but at the end of the day I have nothing to show for it. There's nothing that I can touch and feel, nothing that I can step back and take a critical look at and think, "Nicely done," and to be perhaps overly honest, nothing that I can say that I did for myself. It is for these reasons that I look forward to the weekends.

All of that was torn asunder Friday evening when the Co-owner and I received a phone call from Co-pilot Egg as we were driving home from picking up dinner at a new restaurant near by. The dinner stop in itself was an exercise in patience-taxing frustration as they lost our order and we spent twenty minutes waiting for them to get their act together. Now that wasn't time wasted, mind you. It gave me plenty of time for one of my favorite things to do at a new restaurant, which is to find misspellings in the menu. In this case, I chuckled over 'Hot Gralic Chichen,' but I laughed out loud when I got to 'Garlic Fog Legs.' You know what they say about fog legs: they taste just like chichen!

Anyway, I pretty much knew what the problem with Egg was as soon as I heard her voice. Pretty much any time she's crying her eyes out, it means something has taken a turn for the worse in a relationship. Unfortunately, that was the case this time as well. Her boyfriend, Mr. Case, had called it quits. Some of the Dads of daughters reading this will understand me when I say that this was not one of the "Oh, good!" break-ups for me; no, this is one of the break-ups where I feel like I've been dumped too. I really liked this one. And I have to say, the kid had class. None of this texting or phone call stuff for him - he told her in person, and he stayed with her until we could get home. That could not have been easy.

So, it's a weekend of emotional turmoil in the house, a situation that I responded to in my tried and true manner: I got out of here! I escaped to the hangar with the hope of making some good progress on the canopy. I've been muddling through one of those little jobs that I always underestimate. It seemed easy enough (I say that so often that I ought to create an acronym for it): there are two little plastic blocks that get mounted on the front of the roll bar, their raison d'etre being as mundane as their appearance: they do nothing but ensure that the canopy isn't brought down so out of alignment by a careless pilot or passenger that the canopy skirts get caught up on the fuselage sides.

The little bit of fabrication required should have been trivial; all I had to do was drill two holes through each of the two plastic blocks.  The problem came from one of those little mistakes Van's makes in the plans and steadfastly refuses to fix. Consider this image:

Note that the width of the block is 1/2". Note that the holes are drawn as being positioned right on the centerline. Note that 3/8" from an edge is not going to put that hole on the centerline. Normally I'd just assume that either the drawing or the measurement was in error, and I was leaning heavily to the measurement being in the wrong. Just to be sure, though, I went home and checked on the Van's Air Force forum to see if any of my building peers had run into the same issue. I searched the archives for 'canopy blocks' and found one mention of them, but it had to do with how much material would need to be removed to ensure clearance from an inconveniently positioned nut on the side of the canopy.

I went ahead and posted a query and got a reply from one person that said he had faced the same issue and decided to position the holes on the centerline. All had worked out well for him. Safe in the knowledge that I could proceed without undue risk, I completed the drilling of the blocks. He also mentioned that he had needed to cut away quite a bit of material to get the needed clearance from the inconvenient nuts and he was right: I had to cut away quite a bit of the corner of the block. I tried removing a little at a time, but finally just bowed to the inevitable and sliced off the whole corner.

And, at long last, it was time to start the fiberglass fairing around the canopy. This starts out by shaping a couple of pieces of styrofoam into a shape that will provide a nicely rounded surface for the fiberglass to bond to and cover up the "coves" where the canopy frame forward arms reside when the canopy is closed.

The blocks get trimmed to fit into the cove. The bandsaw made short work of that:

There's going to be epoxy flying around and some of it will drip. So, masking is called for.

This block didn't fit like it was supposed to. The plans implied that this back edge would be flush with the fuselage skin. Not so much:

Pete and I had a meeting and determined that it was pretty safe to just cut away the offending material.

The bolts that the canopy pivots around must remain accessible, so a hole needs to be cut in the foam to allow access to them. The position of the hole is marked by pressing the foam against the bolt head.

The hole gets drilled out with a 7/8" Unibit. My Unibit only goes as large as 6/8" (3/4" for you mathematicians), but that was no problem. The foam is so soft that I was able to spin the bit by hand, then add the additional 1/8" with a small file. We're then supposed to use a Sharpie marker to trace the outline of the upper fuselage against the inboard side of the foam. We had two problems with that: a Sharpie wouldn't fit between the canopy frame, and we couldn't decide what precisely was meant by "upper fuselage." Looking ahead a few pages, it appears that the foam doesn't go any higher that the edge of the canopy frame. I just used a small screwdriver to trace the edge of the canopy frame.

The bandsaw did the rest.

One squirt each of the resin and hardener, plus a couple of tablespoons of flox made a nice paste that was used to glue the blocks in place.

Sunday, September 18, 2011

A Tale of Two Canopies

Canopies: they are the best of airplane enclosures, they are the worst of canopy enclosures, they are works of wisdom, they are works of foolishness, the are the epoch of in-flight visibility, they are the epoch of build complexity, they provide gobs of Light, their construction brings days of Darkness, they are the spring of hope, built just before the winter of despair....

with abject apologies to Mr. Dickens. I have two to deal with, one being attached to a flying RV-6, the other being a recalcitrant detriment to an RV-12 ever taking flight.

The RV-6 canopy was not mine to build and has, if the truth be told, been pretty reasonable when it comes to maintenance chores. Basically over the years it has all come down to cleaning the bugs off of it now and then. Until yesterday, that is.

Yesterday was one of those days that you wish you could squeeze into a ZipLoc back and put on the snack shelf in the pantry to be parceled out as a tasty snack every now and then when the weather gets bad.

I had to fly.

I had to fly!

The choice of destinations was easy: my Dad's birthday is next week and through the accident of ordering a hand drill whose price was lower than the $25 minimum for free shipping from Amazon, I had on hand a book that just happened to be the Y in the equation X + Y = $25.01, where X = hand drill. And a good book it is, too, being one of the multitude of means available (yet ignored) to lawmakers and Supreme Court Justices to help them determine just exactly what the Founders meant when the plain English that they used in writing our Constitution requires "interpretation."  Of course, one cannot expect them to be in need of shipping charge padding in precisely the amount needed to pick up a copy of the Federalist Papers or, in my case, the thousands of words shared between Thomas Jefferson and John Adams.

So it was that I found myself descending into the pattern at Darke County (KTZR) International with 180 mph showing on the speedometer, wondering just what in the world that horrendous slapping/buzzing sound emanating from the bow of the canopy just behind me was. Upon landing I was quickly able to discern the problem: the airplane, which is mad at me for trying to sell it, had decided that it would quite willingly trade away some of the weather stripping around the edge of the back windshield simply in order to irritate me. A ten inch section of the stripping had worked its way loose and was flapping in the hurricane force winds that come with the awesome speeds the RV-6 can attain.

I didn't want to fly it back that way, but an interim solution was easily at hand: I "borrowed" a length of duct tape from the local mechanic. Here it is, still in place and unruffled after the return flight.

There is simply nothing that duct tape can't do, with the possible exception of surgical suturing.

Sunday morning dawned equally gorgeous and thus seemed perfect for the work of finishing up the mounting of the canopy to its frame, and if all went well, the installation of the canopy latch too. Pete was along to help again, so I figured we'd get these little jobs done in no time. The first thing to do was to rivet on the canopy skirts. That took very little time since, as is the norm when riveting, the job went three times as fast with two people working. After that we had to install the screws, nuts, and washers that attach the canopy sides to the frame.

I thought the same kind of division of labor as used in the riveting would ernder the same time-saving results, but it didn't quite work out as well. As Pete was on one side of the canopy getting the screws and nuts in place for me to tighten, I would be on the other side tightening the ones that he had already started. It worked well enough, but every now and then the movements of the canopy resulting from his work would get out of synch with the coffee palsy my hands get after a large McDonald's cuppa and I wouldn't be able to get the screwdriver aligned with the moving screw.

I had the shop radio tuned to the local NPR classical music station in an attempt to elevate the culture of the shop, but that only led to such high level discourse as:

Me: "You know, all of this classical music sounds the same."

Pete: Silence.

Me: "No, really. There's only one piece of classical music that can be readily identified by 99.999% of people."

Pete: "The 1812 Overture?"

Me: "Hmm, no, I was thinking Beethoven's Fifth, but you might be right about the 1812 Overture too. Although I imagine most people don't get it until the cannon fires."

See? More cultured already!

It was right after that burst of intellectualism that we noticed something. Pete pointed out that the directions called for me to "cut off the threads that protrude beyond the end of the nut " on the most aft screw on each side. Fortunately, we were all brained-up on classical music and recognized the word "protrude." Still, it seemed odd to cut off all of the threads, what with the standard airworthiness measurement being at least two threads sticking out protruding from a lock nut.

A closer reading showed that we were to consult the figure on the following page for more information. It's good that we did!

That was a job for the Dremel.

That finished the mounting of the canopy, so we pressed on with the installation of the latch. The first thing to do there was to insert the D-handle through the tube in the canopy frame. If the handle was loose enough in the tube that it could rotate on its own accord with no more motive force than the weight of its handle, I was to "carefully pinch" the ends of the tube. The handle did, in fact, rotate quite freely, so I proceeded to pinch the end of the tube, but apparently not carefully enough since the handle would then no longer fit into the tube at all.

This left me with the perplexing quandary of how exactly one goes about un-pinching a tube. As it turns out, that can be accomplished by inserting the end of a large drill bit slightly into the tube and using it as a kind of pry bar to separate the sides of the tube back out. It might also require a little cleaning up with a small file. After fiddling with it for a little while, I got it to a state where the handle would fit through the tube and turn only with physical motive force.

All that remained was to attach the handle, which I had placed somewhere where I wouldn't lose it. And we all know what that means. As we were hunting for it, I cupped a hand to my ear and said, "Oh, there it is! It's in the radio!"

 To which Pete, quite naturally, said, "Huh?"

"Oh, never mind," I replied, "that's Handel, not 'handle'."

And that was that for any hope of elevated culture.

That done, the matching latch parts needed to be installed on the roll bar. The first part is a Teflon-esque plastic block that will provide a soft-ish latching mechanism for the handle to latch into. The holes in the roll bar need to be tapped to 8-32 to provide two holes for the screws that will hold the latching block in place to screw into. This operation entails a number of steps that seem somewhat make-work and silly until you realize that the entire purpose of them is to get the tap perfectly straight as it works its way into the roll bar. One wonders why they don't just tell us why we're doing odd things now and then.

That was all going swimmingly (even though we had yet to figure out why we were going through all of the seemingly silly steps) until it came time to cleco the latching block into the two holes in the roll bar that were mysteriously left open wwwaaayyyy back on page 24-05.

I had left the wrong two holes open:

In my defense, when I was wwwaaayyyy back on page 24-05 I didn't have the drawings and parts that I have now, and the quality of the drawing that I had to work from was somewhat less than could be desired.

So, out came the mistakenly placed rivets and in went the new. Screwing and tapping and more screwing ensued.

We did a quick test fit of the latching handle and found that it wouldn't fit into the latch block. The plans allow a .020" removal of material from the latch, so I worked on it for a little while with a small file.

Upon a second test, I made an interesting discovery. I discovered that it is possible to get the canopy latch to latch, but to be completely unable to get it to un-latch. Luckily for me, I had a Sharpie(tm) marker in there with me and was thus able to communicate with the outside world:

The latch proved to extraordinarily difficult to get working properly, but we eventually tracked the problem down to the outside handle holding the D-handle up too high. That was caused primarily by a slightly off-center drilling of the screw hole that holds it onto the shaft of the D-handle. There were a number of possible solutions that we kicked around, all of which involved re-ordering parts or trying to remove material from the parts on hand. A consultation of the Van's online store showed the following:

Ruin this part:         Buy a new one for:

plastic block                $8.50
outside handle             $16.00
canopy frame              don't even ask

Neither of us wanted to be considered cheap, nor did either of us want to re-build the entire canopy on a new frame so we decided to concentrate our efforts on the handle. With that level of decision-making prowess brought to bear, we soon decided that I would remove 1/16" off of the bottom of the outside handle. The band saw was perfectly capable of that, although that handle got so hot that I was able to use it to finally defrost the little freezer portion of the hangar fridge. Still, it solved the problem!

Everything else fit perfectly and was in reasonable alignment. I was happy to see that the canopy skirts overlapped the fuselage sides perfectly and didn't require the installation of any spacers.

There are a couple of more little plastic blocks to install, and then the fiberglassing begins. This was the point where I had decided that I'd place my order for the engine, but I think I'm going to hold off for another couple of weeks. I don't foresee the fiber glass work going all that quickly.

Wednesday, September 14, 2011

Just screwing around

I officially start dreading winter on June 21st of each year, mostly because I have a thirty-five mile commute each way to and from the paying job, and nothing can mess up and already annoying drive like winter weather. But I also dread the onset of the latter half of the year because of the loss of evening light. Working under the single hangar light is a dreary, mood-sapping thing, and the encroaching shortened days are nothing that I look forward to with any sense of well-being.

So, this is the season of shortened work sessions on weeknights. It's bite-sized jobs I'm looking for this time of year, or larger jobs that can be sliced up into smaller segments. This job slicing is what I'm doing with the job of mounting of the canopy on the canopy frame.

I'm getting a little ahead of things, though. Before starting on the mounting of the canopy, Pete and I had to backtrack a little bit to finish the installation of the locating tabs that I failed to do before removing the frame for painting. It wasn't a particularly difficult job and wasn't too long before we were ready to start the canopy mounting.

Looking at the drawing in the plans, it looked like there were a dozen exotically nomenclated (why yes, I do believe I did just now invent that word) rivets, screws, nuts, and washers involved. In reality I think it was actually only three different types of rivets, but it was a somewhat daunting drawing nonetheless. In situations like this I often leverage my skills in the occult to divine the meaning buried in the hieroglyphs of the plans, usually through haruspicy (no, I didn't make that one up) but as luck would have it, the oftentimes over-industrious co-owner had accidentally disposed of the leftover chicken entrails that I had set aside for precisely this purpose.

I figured we'd just have to muddle through with whatever raw human intellect we could summon forth, but luck was on my side, albeit at first glance it seemed to be a misfortune. Having been somewhat careless in the setting down of the canopy frame on the workbench, I managed to spill my container of LP4-3 rivets. It only took a glance for me to see the power of the dark forces at work: it would be just like reading tea leaves:

It only took a few minutes of divination to figure out the solution to the rivet problem. As usual, the answer was.....

...let Pete figure it out.

While he busied himself with that, I installed the row of screws, washers, and locknuts across the aft bow of the frame.

This time of year is also a busy time for my other writing tasks as requests for game reviews start to pour in as the Christmas shopping season starts to wind up. It'll probably be a few days before we take the next bite out of the canopy work.

Sunday, September 11, 2011

Distraction Season

Do you remember the classic Bugs Bunny and Daffy Duck vignette where they are each trying to convince Elmer Fudd that it is open hunting season for the type of animal each is not?

Bugs contends that it's duck season, and Daffy insists that it's rabbit season, up until Bugs switches up the order and tricks Daffy into convincing Mr. Fudd that it's duck season.

I'm here to tell you that they both had it wrong: it is, in fact, distraction season.

Fall is one of the best times of year, as far as I'm concerned, but it often offers up a veritable cornucopia of things that distract me from building the RV-12. Co-pilot Egg is back in school for her senior year, and that brought a school open house and the never-ending chore of trying to get her started on her college applications.

It's also football season, and that means Saturday afternoons either stressing through agonizing losses or yawning through complete blow-outs. I suspect that we're in for more of the former than the latter this year, although Saturday's game was set up to provide the type of exciting down-to-the-wire finish that makes it worth sitting through the game. With a minute and a half left and a five point lead, O$U had to stop the Toledo Rockets from scoring. It was beginning to look grim as Toledo continued to march down the field, but with 90 seconds to go the co-owner, who was sitting in front of a laptop computer, blurted out, "Don't worry; we win."

When you consider that I leave the room after a TV show finishes because I don't want to see or here the scenes from next week, well....

It's also shooting season. That means Sunday mornings are more often than not going to include either sporting clays or skeet shooting. It was sporting clays today. You may remember that my scoring trending as of the end of the season last year was horribly downward. I had one really good round of 21/50 when I bought my new shotgun, but the rounds after that were 9/50 and 8/50. It was obvious to me that the only strategy that worked was to buy a new shotgun every week, but the co-owner, not unreasonably, put the kabosh on that idea. No, I'd have to improve the old-fashioned way: practice. You may also remember that I did just that by buying and using my own trap. The last time I practiced, I was able to string together series of ten to fifteen hits before missing a clay. That practice paid off today with a respectable 16/50. There's obviously a lot of room for improvement, but I was happy with such a reasonably good start.

Squeezed into all of that activity was watching one of the best Formula 1 races of the year at the historic and incredible track in Monza, Italy, and doing some small jobs on the RV-12.

The next big step in the RV-12 process is the attachment of the canopy to the canopy frame, but there are some smaller jobs to be knocked out first. The first of those was the fabrication of the handle that will allow the latching and unlatching of the canopy from outside the airplane. Having not been to the hangar for a full week, I had to spend a few minutes working up mental acuity through the expedient of ingesting caffeine and perusing the plans.

It starts out easily enough. The first thing to be done was to measure and place a spot in the very middle of the handle. Finding and marking these spots is a common task in the RV-12 build, and the purpose of them is to make it graphically obvious how far off-center the hole you will eventually drill will be.

The handle was to be placed on the steel rod extending from the handle assembly that will be used to latch and unlatch the canopy from inside the airplane. As usual, the hole that Van's drilled into the handle is exactly the same size as the rod that's supposed to fit into it, which means.... it won't.

Fit, that is.

In order to make it fit, I resorted to using my Harbor Freight heat gun (Harbor Freight, The Home of Cheap Electric Tools That Are Hotter Than the Sun, Sometimes Deliberately) to expand the aluminum handle so that it could be tapped into place on the rod.

That allowed me to drill the requisite hole through the rod and further into the handle.

Then, the most dreaded of words: "Disassemble." That, in a word, sucked.

I had one heckuva time getting that handle back off of there, even with the assistance of the heating tool. Once I was able to finally get the handle back off, I followed the suggestion of Van's to optionally round off the corners.

With that done, the handle gets cast aside in preparation for ultimately losing it, while attention shifts to the painting of the canopy frame. I've been having trouble getting paint to stick to the material that is used in the roll bar and canopy frame, so this time I gave it a good scratching up with some 220 grit sandpaper.

Then it was back to the little jobs. There are a couple of plastic blocks that get mounted into the canopy frame that will act as centering guides when the canopy is being closed. They're held in with two 8-32 screws each, and the holes for those screws needed to be tapped. At long last, I have found a material that is softer than a Harbor Freight tap!

Here is the tab that will be mounted to the canopy frame, sitting down in the slot. Why is it sitting here and not on the canopy frame? Well, there was a step for that - the tab gets aligned and match-drilled to the canopy frame while it is still installed on the airplane; I thought that since I didn't want this tab to get painted, I would remove the canopy frame for painting first, then install the tab. In hindsight, this was stupid. It's not like I don't have any masking tape, after all. I removed the canopy frame and painted it, then realized that I needed Pete's help to put the frame back on the airplane in order to correctly position this tab. Once that's done, the canopy frame will then immediately get removed again to attach the canopy to it.

Rather than pout about it, I pressed on with the fabrication of the little tabs that will act as lift handles for opening and closing the canopy. They start out as 1 13/16" pieces of aluminum angle, but through a few steps become nice looking little handles.